Optically triggered semiconductor device and method for making the same

Abstract

A thyristor device includes a semiconductor body and a conductive anode. The semiconductor body has a plurality of doped layers forming a plurality of dopant junctions and includes an optical thyristor, a first amplifying thyristor, and a switching thyristor. The conductive anode is disposed on a first side of the semiconductor body. The optical thyristor is configured to receive incident radiation to generate a first electric current, and the first amplifying thyristor is configured to increase the first electric current from the optical thyristor to at least a threshold current. The switching thyristor switches to the conducting state in order to conduct a second electric current from the anode and through the semiconductor body.

What is claimed is: 
     
       1. A method comprising:
 providing a semiconductor body extending between opposite first and second sides, the semiconductor body including doped layers that form first and second dopant junctions located between the first and second sides; 
 removing a first portion of a first layer of the doped layers that is disposed along the first side of the semiconductor body to expose a second layer of the doped layers, the first portion of the first layer removed to provide an activation portion of the semiconductor body that receives incident radiation to generate electric current in an optical thyristor of the semiconductor body; 
 removing a second portion of the first layer of the doped layers to expose the second layer in an intermediate portion of the semiconductor body, the intermediate portion disposed between an amplifying thyristor and a switching thyristor of the semiconductor body; 
 conductively coupling a conductive terminal between the first layer in the amplifying thyristor of the semiconductor body and the second layer that is exposed in the intermediate portion; and 
 conductively coupling an anode to the first layer of the doped layers and a cathode to the doped layers at the second side of the semiconductor body. 
 
     
     
       2. The method of  claim 1 , wherein the activation portion of the semiconductor body is configured to receive the incident radiation into a gate of the optical thyristor to switch the optical thyristor to a conducting state. 
     
     
       3. The method of  claim 1 , wherein removing the second portion of the first layer of the doped layers to expose the second layer in the intermediate portion of the semiconductor body prevents current from flowing between gates of the amplifying thyristor and the optical thyristor. 
     
     
       4. The method of  claim 1 , further comprising creating an isolation region in the second layer in the intermediate portion of the semiconductor body, the isolation region configured to prevent current from flowing between gates of the amplifying thyristor and the optical thyristor. 
     
     
       5. The method of  claim 4 , wherein creating the isolation region includes etching a void into the second layer in the intermediate portion of the semiconductor body. 
     
     
       6. The method of  claim 4 , wherein creating the isolation region includes counter doping a portion of the second layer in the intermediate portion of the semiconductor body. 
     
     
       7. The method of  claim 4 , wherein removing the second portion of the first layer of the doped layers to expose the second layer in the intermediate portion of the semiconductor body is performed in a ring that encircles the activation portion of the semiconductor body.